I've dealt with a spate of cardiac arrest calls recently, where the patient has been in a state known as PEA - Pulseless Electrical Activity; in other words, there's little or no output, but there is still electrical activity within the myocardium. PEA produces waveforms that are similar to normal electrical impulses when the heart is beating, except they tend to be slower than normal because the heart muscle is struggling to cope with a lack of blood and oxygen, as is the brain and so there is much less electrical activity than normal.
However, in at least six cases over the past few days, where elderly patients have been in slow PEA for quite some time (up to an hour), with CPR ongoing and Adrenaline being given by extremely competent crews, and where the teams in question requested permission to terminate the resus on the basis of futility - not long after it was 'called' and given a time for Recognition of Life Extinct (ROLE), the crews reported a return of spontaneous circulation (ROSC). In other words, shortly after compressions ceased, the patient's heart began to beat. This occurred in every one of those patients despite every causative avenue having been explored prior to cessation of resus and a call, in conference to the Clinical Support Adviser and a senior doctor.
Adrenaline, of course, is a major factor here. This hormone can 'make a stone beat', according to one of my doctor colleagues, and I've seen this on many occasions myself (the effect of adrenaline that is), but what I'm thinking about is the possibility that something is happening that could be relevant to the difference between a loved-one dying on the carpet in the front room, or in a hospital bed, with enough time given to say goodbye.
Are we inadvertently creating a ROSC by NOT continuing CPR, or was there a pulse there at the time, during compressions? We continually compress the chest now; there are few pauses and rests, so could there be a reason so many PEA-ROSC outcomes are being recorded?
To be honest, I don't know and I'm hoping that someone out there has had more experience of this and can give me something more to go on than 'it's just one of those things'.